Reporter genes are important tools that enable researchers to study DNA sequences that regulate gene expression. Light emitting proteins, such as luciferases, are useful reporter genes since the amount of protein produced can be measured as light output. Luciferase genes have been isolated from a variety of organisms such as insects and a variety of marine organisms. The luciferase gene from the sea pansy (Renilla reniformis) is a widely used luciferase reporter and is commonly referred to as “Renilla”. 
Marine luciferases have become popular alternatives to firefly luciferase as a genetic reporter based on assay simplicity, high sensitivity, and a broad linear range of signal that provides greater sensitivity over firefly luciferases. The Renilla luciferase protein catalyzes oxidation of its coelenterazine substrate in the reaction shown below to produce light at 480 nm, easily read by standard luminometers. U.S. Pat. No. 5,418,155 (CORMIER, M. J. et al., May 23, 1995) provides an amino acid sequence of Renilla luciferase and a nucleotide sequence encoding it. U.S. patent application 2006/0068395 (WOOD, K. V. et al., Mar. 30, 2006) provides another nucleotide sequence encoding Renilla luciferase.